Acetylene generator



Jan. 23', 194 M. P. 'DE MOTTE 2,188,278

ACETYLENE GENERATOR Filed July 17, 1937 INVENTOR ATTORNEY Patented Jan. 23, 1940 UNITED STATE aissgas ACETYLENE GENERATOR Maurice P. De Mott, Indianapolis, ind, assignor to oxweld Acetylene Company, a corporation of West Virginia Application July 17, 1937, Serial No; 154,159

This invention relates to acetylene generators and more particularly to the carbide feeding mechanism of acetylenegene'rator's of the carbide-to-water' type.

The novel features of this invention are particularly adaptable for use with the improved carbide feeding and gas pressure control mechanism for acetylene generators of the carbide-towater type disclosed in Patent No. 2,106,972 granted to M. P. De Motte on February 1, 1938, of which this is a continuation-in-part.

The supply of carbide to the gas generating chamber of these generators is usually automatic'ally controlled by the pressure of the generated gas. A pressure responsive diaphragm is pro vided which, on one side, is exposed to the pressure within the generating chamber. The opposite side of this diaphragm is engaged by a spring, the expansive force of which may be. adjusted to a predetermined operating pressure. Often, this force is so great that a considerable amount of effort is required to close the carbide feed valve when it is desired to interrupt the generation of acetylene and the valve operating mechanism may be unduly strained. To overcome this difficulty, in the generator described in the above pat em, a lost motion connection is desirably provided between the carbide feed valve and the pressure responsive diaphragm.

However, when an acetylene generator stands idle for any length of time, moisture in theatmosphere withinthe generator body may cause a slight slaking of carbide at the mouth of the hopper outlet. The moist carbide residue resulting from this s'laking' action tends to cause a sticky condition between the carbide valve and the valve seat. In generators of the type disclosed in the above-identified patent, and wner'e-' in the force of gravity acting on the lever and Valve is relied u ento overcome-the 16st fr'lotiil between the carbide fd valve and the dia phragm when the generanen or aeet lfie is re"-.

Slifnd, the sticky conditionrneiltiofid above may valve to its fullextent or hold it open too long a ing the generation of acetylene, the automatic time, thereby permitting an excess of carbide to enter the generating chamber and consequently cause a rapid rise in pressure before the control mechanism becomes effective. Means must therefore be provided to automatically prevent an ex- These and other objects ofthe invention will I in part be obvious and inpart become apparent from the following description whenread in conjunction with the accompanying drawing, in

which: Fig. 1 is a view of a generator with which the improved carbide feeding mechanism is to be used;

Fig. 2 is a sectional view taken on the line 2 -2 of Fig. 1; and

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2, and illustrating the improved carbide feeding mechanism of the invention.

-'The invention, as illustrated in the drawing, may be embodied in an acetylene generator of the carbide to-Water type, described in the aboveidentified patent and which may include a closed casing of symmetrical contour having a watercontaining and gas-generating lower portion A and a somewhat smaller carbide-containing and gas-storage upper portion B. The upper end of the lower portion Amay taper inwardly and-upwaidly so as to merge with the upper portion B which may be provided with a conical top C. In order to provide access to the interior of the generator, the meeting portions of sections A and B may be respectively provided with separable flanges l0 and I2 suitably joined by conventional means such as a plurality of bolts l4, and appropriate hinges l5. l

The upper section B may also be provided with a suitable compartment or chamber D within which the accessory equipment, with which such generators are usually provided, may be enclosed and protected by a suitable closure such as doors l6 and i8.

The compartment D is preferably within the general outline of section B, with which the doors l6 and I8 substantially conform. The generator may be further provided with conventional features such as a carbide charging door 20, gasable depending spout having a carbide outlet opening 42 therein. For convenience in attaching adjacent accessories and to facilitate removal of the outlet, the spout 46 may be secured to an annular hopper casting or ring 44 by suitable means such as a plurality of bolts 46, and the ring 44 may in turn be rigidly secured along a suitable opening in the bottom of the hopper by conventional means, such as a weld 48. The lower portion of the spout may be provided -with a drip flange 50and this flange may be provided with an internal annular groove 52 ad jacent and below the outlet 42, in which an annular compressible valve seat 54 of soft rubber or the like is removably secured by a supporting retainer plate 56 and an interfitting spring ring 58. The opening in the annular valve seat 54 'maybe of substantially the same size and substantially in alignment with the outlet opening 42 with which it cooperates and forms a part, and the flow of carbide from within the hopper to the outlet opening may be controlled by a carbide valve 60 that seats on valve seat 54 and forms a fluid-tight seal through which no water or moisture can enter the hopper and cause generation of gas when the valve is closed. The carbide valve may form' a part of a carbide-feed and gas-pressure control mechanism F which may be detached from the generator as a unit. As the control unit F is fully described in the above-entitled patent, no further description is believed necessary here except to state that it includes a flexible diaphragm 62 upon which the gas pressure within the gener ator is balanced by one or more expanding springs, such as 64 and 66, which springs may be compressed within a suitable housing '68 in operative relation with the diaphragm which inturn is operatively connected with the carbide valve 60;' The desired operating pressure imposed on the springs 64 and 66 is adjusted by means of an adjusting screw I0 which operates on the springs 64 and 66 through a movable spring pressure plate I2. At the opposite end, the springs 64 and 66 engage a second spring pressure plate 14 which cooperates with the flexible diaphragm 62.

One of the features of the present invention resides in an improved connecting means between the diaphragm 62 and the carbide feed lever 80, to the inner end of which is pivotally secured, as by a pin 82, the carbide valve 60. An

. inner plate 84, in engagement with the pressure plate 14, and an outer plate 86 are secured, by means of a bolt 88 and a nut 90, to the diaphragm 62. The bolt 88 is formed with a forked end 92 in which is pivotally secured, as by means of a pin 94, the inner'end of a'link 96. In the outer end of the link 98 is cut a slot 98 receiving a pin I00 attached to the carbide feed lever 86. The slot 98 and pin I00 form a lost motion connec tion between the diaphragm and the carbide feed lever.

The lever may be pivotally mounted on a suitable pivot pin I02 extending across an appropriate slot formed by lugs I04 of a feed lever support I66 that may be integral with a flange ring I08. This flange ring is secured by suitable means, such as a plurality of bolts I I 0, to an outwardly offset flange II2 formed on the inner end of housing 68. The diaphragm 62 is clamped between ring I08 and flange II2.

A spring seat I I4 is formed on the carbide feed lever 80, and a resilient member such'as a spring II6 surrounds the lost-motion connection and extends between this spring seat and the plate 86, tending to urge the pin I00 to the right in slot 98. An equivalent form of valve-operating mechanism including a lost-motion connection surrounded by a spring, is described and shown but not claimed in the copending application of Maurice P. De Motte et al., Serial No. 138,752, filed April 24, 1937.

For the purpose of holding the carbide valve closed when desired, such as when the generator is moved or when it is recharged, suitable means may be provided for operating the valve manually. This manual operating means may include a valve-closing arm or locking lever II8 integral with the lever 80, and in operative relation with a rotatable member such as a cam I20 formed with suitable cam surfaces I22, I24, and I26, and a lug I28 which forms part of an interlocking means preventing the maximum opening of the valve 60 until a predetermined pressure has been established in the generator. Cain I20 is fixedly mounted on an operating shaft I30, one end of which is provided with a suitable manually movable member, such as a handle I32 which is preferably located outside the generator casing within the accessory compartment D. The shaft I30 is mounted in a bearing. I34 which may be integral with the spout 40.

In the position of the feeding mechanism will be under compression and the pin I00 will beat or near the right hand end of the slot 98. If the generator remains idle for a considerable period of time, or if the residual gas is drawn off, the drop in gas pressure will permit the springs 64'and 66 to force the diaphragm 62 to the right. The feed lever 80 remains stationary, so the pin I00 will move to the left relative to the slot 98 in the link 96.

If it is desired to resume the feeding of carbid'eto the generating chamber, the cam' I20 is rotated counterclockwise. The initial movement of the cam is limited by engagement of the lug or stop I28 with the end of arm 8 so that the cam surface I24 is disposed beneath this arm, thereby limiting the opening movement of the valve 60. The small amount of carbide permitted to enter the generating chamber by the initial opening movement of the valve 60 reacts with the water therein to generate acetylene gas at a rate just sufficient to cause the pressure to slowly increase. As the pressure rises within the generating chamber, the diaphragm 62 is moved to the left and closes the valve 60. The arm I [8 will then have been moved upwardly to its full extent and in this position the cam I20 The residual pressure in the may be further rotated in a counter-clockwise direction to move the ug Hi8 beneath the arm I I8 and past the same, and brihg th carn: surface I26 to a position below the arm H8. when this last cam surface" s disposed below the arm 8, the valve may open to its fun extent and is then fully under control of the automatic feed control unit.

When it is desired to" stop the generation or acetylene gas, the operator will rotate the cam I20 clockwise until the cam surface 122! trikes the arm Ha forcing this arm upwardl and closing the feed valve fifl. In this' operation, the force of the springs as and 66' will not hat/etc be overcome as the pin lnomay move to the left in the slot 98 compressihg the spring H G. The spring H is of ummer-1t rigidity to take up all play in the lost motion connection and to insure that a positive opening movement of the valve will take place when the locking mesh anism is released. This will force the valve away from the valve seat even though a slight slaking of the carbide may tend tocause a sticky condition between the valve and the valve seat.

Thus, when this spring is used, gravity is not relied upon to open the valve 60.

The lug I28 is o-f'sufiicient height to prevent the cam I20 being turned to' allow the: valve to to become fully open until the gas pressure in the generating chamber is suificient to cause the automatic control mechanism to function. When the gas pressure has reached this predetermined value, the cam I20 may be turned further in a counter-clockwise direction, as explained above, and the valve will then be fully under the control of the automatic mechanism.

The above-described mechanism retains the advantages of the lost motion connection, which permits the valve to be closed without overcoming the full force of the springs 64 and 66, while insuring a positive opening of the valve under all conditions. By the use of the spring H6 disposed between the diaphragm 62 and the lever 80, desirable features of the lost motion mechanism may thus be retained without the disadvantage due to the lack of a positive connection between the feed lever and the diaphragm.

Although the various features of the improved generator have been shown and described in detail to fully disclose one embodiment of this invention, it will be evident that numerous changes may be made in such details and certain features may be used without others, without departing from the principles of the invention.

What is claimed is:

1. An acetylene generator including in combination, a hopper having an outlet; a valve controlling such outlet; means responsive to a predetermined gas pressure within such generator for controlling the operation of said valve; and means for preventing the. maximum opening of said valve at least until said predetermined pressure has been established within said generator, said means comprising a pivotally mounted lever connected to said valve and to said pressureresponsive means and a rotatable cam for engaging said lever, said lever and said cam being provided with interlocking means for preventing rotation of said cam to a position permitting the maximum opening of said valve before said predetermined pressure is established.

2. An acetylene generator including in combination, a hopper adapted to contain calcium carbide and having an outlet; a valve controlling said outlet; a pressure-responsive diaphragm mounted in said generator; a lever pivotally mounted on said generator; said lever being ivotally connected to said valve and connected to said diaphragm through a lost motion connecf tion; and a spring bearing against said lever and said diaphragm and surrounding said lost motion connection.

3. An acetylene generator as claimed in claim 2, including means engaging said lever for locking said valve in its closed position, said means being rotatable to a position in which said valve may open a' limited amount and including a stop for engaging said lever to prevent further ro-' tation of said means until said valve has been closed through the action of said pressure re spons'ive diaphragm. l

4. An acetylene generator as claimed in claim 2, including a rotatable member for engaging said lever and locking said valve in closed position, said member being rotatable to a position in, which said valve may open a limited amount and including a stop for engaging said lever to prevent further rotation of said member until said valve has been closed by said pressure re spons'ive means; said stop being of a height suf ficient to permit it to pass said lever when said valve is closed, whereby said member may then be rotated to a position in which said valve may open to its full extent. v

5. An acetylene generator as claimed in claim 2, in which said lost motion connection includes a link, said link being connected to said diaphragm by a fixed pivot and to said lever by a slot and pin connection.

6. An acetylene generator as claimed in claim 2, including means for locking said valve in closed position; said spring acting to force said lever away from said pressure-responsive diaphragm to positively open said valve when said locking means is released..

'7. An acetylene generator as claimed in claim 2, in which said lost motion connection includes a link connected to said diaphragm by a fixed pivot and to said lever by a slot and pin connection; means for locking said valve in its closed position; said lost motion connection permitting said spring to be compressed between said diaphragm and lever when said valve is locked in its closed position; and said spring expanding to force said lever away from said diaphragm to insure positive opening of said valve when said locking means is released.

8. An acetylene generator including in combination, a hopper adapted to contain calcium carbide and having. an outlet; a valve controlling said outlet; a valve lever pivotally mounted within said generator and pivotally connected to said valve; a pressure-responsive. diaphragm mounted in said generator; said valve lever being connected to said pressure-responsive diaphragm through a linkage including a slot and pin connection; a spring bearing against said diaphragm and said valve lever and surrounding said linkage; an arm rigidly secured to said valve lever; a manually rotatable cam mounted below said arm; said cam including a cam surface adapted to engage said arm and lock said valve in closed position, a cam surface adapted to permit limited opening movement of said valve, a stop adapted to engage said arm, and a cam surface adapted to permit full opening movement of said valve.

9. An acetylene generator including in combination, a hopper adapted to contain calcium carbide and having an outlet; a valve controlling lever connecting said valve and said diaphragm; an arm extending, from said lever; rotatable means for engaging said arm and locking said valve in closed position, said rotatable means including a member adapted to engage said arm and limit initial rotation of such rotatable means to prevent full opening movement of said valve until the pressure within. said generator has reached apredetermined value.

10. An acetylene generator as claimed in claim 2, including means for engaging said lever to lock said valve. in closed position.

11. An acetylene generator as claimed in claim 2, including means for engaging said lever to lock. said valve in closed position, said means being adapted to move said lever toward said diaphragm and to compress said spring.

12. An acetylene generator as claimed in claim 2, including means for engaging said lever to lock said valve in closed position, said means being adapted to move said lever toward said diaphragm and to compress said spring, and said spring being adapted to move said lever away from said diaphragm when said locking means is released to insure positive opening of said valve.

13. An acetylene generator including in combination, a hopper adapted to contain calcium carbide and having an outlet; a valve for controlling said outlet; a pressure-responsive diasaid outlet; a-pressure-responsive diaphragm; a

phragm; a lever mounted on said generator and pivotally secured to said valve and to said diaphragm; an arm integral with said lever and extending therefrom; a rotatable cam disposed in operative relation to said arm; said rotatable cam including a first cam surface adapted to engage said arm and lock said valve in closed position, a second cam surface adapted to permit said valve to open a limited amount, a third cam surface adapted to permit said valve to open to its full extent, and a lug extending outwardly from said cam between said second and third cam surfaces and adapted to engage said arm to prohibit further rotation of such cam until the pressure within said generator has reached a predetermined value.

14. An acetylene generator including in combination, a hopper having an outlet; a valve controlling said outlet; a pressure-responsive diaphragm so positioned as to be affected by the gas pressure in said generator; means for looking said valve; means operatively connecting said diaphragm and said valve, said means including a lost motion connection whereby said diaphragm may move when said valve is locked; and a resilient member normally opposing said lost motion connection and being of suflicient rigidity to move said valve when said locking neans is disengaged.

MAURICE P. DE MOTIE. 

